No one? Today I couldn't switch to desktop when I started the computer. I had to CTRL+ALT+DEL to open task manager which switches to the desktop.

Well, just as a temporary solution you can use the Win+D shortcut to get you there a bit faster.Would it be possible for you to take a procmon? Download procmon.exe (http://technet.micro...s/bb896645.aspx) then start it up, go to your Start Screen, and attempt to access the desktop. If it fails, press Win+D then File -> Save... all events as a PML file and upload it to Neowin. That way we know exactly where it failed and what it was doing when it failed.